Roy Williams has led the Tar Heels to two national championships but an NCAA investigation is complicating his future -- and that of the program -- in Chapel Hill.

The SI.com Successor Series examines who might replace some of the biggest head-coaching names in college basketball when they inevitably leave their posts. It is intended as pure speculation -- food for thought and fodder for discussion in the long hoops offseason. That said: Down the line, we reserve the right to claim we knew it all along.

Before 2014, the dynamic of succession at North Carolina might not have caused an eyebrow to flinch. It seemed a fairly routine matter – at least as routine as hiring someone to replace a Hall of Fame head coach and run one of the most prestigious jobs in the country can be.

Williams, who turns 64 in August and is under contract through 2017-18, seemed poised to coach for as long as he wanted to at his alma mater in Chapel Hill. Whenever he decided to step down, the mad rush to get in line for his seat would be on. And then the NCAA got involved, with the announcement on June 30 that it would reopen its 2011 investigation into academic irregularities at the school. This after former Tar Heels guard RashadMcCants went public to ESPN in June saying he got through school thanks to a dose of academic fraud and that Williams was aware of what was going on. Williams vehemently denied the allegations.

It is a long way between what McCants has alleged and proving that Williams had any hand in malfeasance, but the future of North Carolina basketball leadership is nonetheless murkier now. Will Williams be able to chart his own course out of town years from now? If not, how does that alter the list of candidates to replace him, if at all? If the restarted NCAA investigation results in a hammer dropping on the hoops program, would that scare top candidates away?

And all that doesn't even touch a different part of this dynamic, which will be true whether or not the program is in trouble: It will be arguably the first time in more than 60 years that North Carolina has to conduct a real coaching search with no slam-dunk candidate atop the wish list. Dean Smith (in 1961) and Bill Guthridge (in 1997) were promoted from within and Williams himself was the school's top choice in both 2000, when he said no (the job went to Matt Doherty, who lasted just three years), and in 2003, when he said yes. Not since Frank McGuire was hired in 1952 has UNC had to go outside its own network to find a head coach, but that may well be what's required whenever Williams steps aside. This time there are no obvious candidates with an unimpeachable resume like Williams had developed at Kansas. Those who might be contenders anyway are presented below, in alphabetical order.

If Williams left tomorrow

Mark Few, Gonzaga head coach. He has won 80 percent of his games in Spokane and made the NCAA tournament every season since taking over in 1999, and he most likely will never coach anywhere else. But Few, who turns 52 this December, also hasn't taken Gonzaga beyond the Sweet 16. Assuming any NCAA issues in Chapel Hill are relatively endurable, negligible or non-existent, would Few view going to Carolina as his one chance to run a blueblood program and reach the heights he has yet to achieve?

Gregg Marshall, Wichita State head coach. A Greenwood, S.C., native, Marshall coached at nearby Winthrop before moving on to Wichita State, where he famously led the Shockers to the Final Four in 2013 and then a 35-0 start that ended in a Round of 32 NCAA tournament loss to Kentucky last March. He has won 70 percent of his games as a head coach and has absolutely zero ties to Williams or the North Carolina program, which may work in his favor should the job open sooner than later. He has it very good at Wichita State, with a salary approaching $2 million. Obviously he'd have more resources and one of the biggest platforms conceivable in Chapel Hill, and it's hard to see Marshall turning that down under normal circumstances. A program crippled by NCAA sanctions wouldn't be normal circumstances, though, and that's the major asterisk.

Thad Matta, Ohio State head coach. Undoubtedly North Carolina will think big, and Matta surely qualifies as someone who can win big. He took Xavier to the Elite Eight in 2004 before he moved on to win 77 percent of his games with the Buckeyes. Ohio State finished as NCAA tournament runners-up in 2007 and reached the Final Four in 2012, following that with an Elite Eight berth in 2013. He has scored big recruits, most notably Greg Oden and Mike Conley (ranked No. 1 and No. 18, respectively, by Rivals in 2006) and Jared Sullinger (No. 5 in 2010). Like Marshall, Matta has zero ties to North Carolina and his only regional connection is the season he spent as an assistant coach at Western Carolina. Otherwise he has been a Midwest guy his entire career, but odds are his track record of winning and successfully wooing elite players would render that a non-factor.

Steve Robinson, North Carolina assistant coach. If Williams really did have to leave at a moment's notice -- like, actually tomorrow -- there is logic in turning over the program to Robinson, who has spent 18 years as a Williams assistant and who previously served as head coach at Tulsa and Florida State. Perhaps Robinson would get a chance to prove himself in the job, but he turns 57 this fall and, in any other circumstance, it's difficult to see a marquee program like North Carolina elevating its top assistant to the full-time head coaching spot without conducting a full, exhaustive search that includes bigger-name candidates.​

Shaka Smart, VCU head coach. Smart, 37, would be a crisp and charismatic leader for any program after winning 75 percent of his games with the Rams and leading them to the 2010 Final Four. He is also a proven winner with enough cachet to deflect the pressure of following a legendary coach, and his personality and relentlessly positive outlook could help shepherd the program through any possible punishment levied by the NCAA. The only question is Smart's ability to consistently recruit at an elite level. His high-pressure “Havoc” defense would make things exciting on the court even if scholarships take a hit, and his track record of winning with players who weren't the highest-rated talents would be a plus.

Long-range plans and longshots

Scott Cherry, High Point head coach, Jeff Lebo, East Carolina head coach, Wes Miller, UNC-Greensboro head coach and KingRice, Monmouth head coach. These four guys are lumped together because their profile is the same. All four have the North Carolina “family” pedigree as former players, which carries a lot of weight in Chapel Hill, and all four are relatively young: Cherry is 43, Lebo 47, Miller 31 and Rice 45. None, however, have produced anywhere near the kind of results that wold make their alma mater take notice. Cherry has a losing overall record in five seasons at High Point, Lebo hasn't taken a team to the NCAA tournament in 16 years as a head coach, Miller is just 34-51 in three seasons in Greensboro and Rice is merely 33-62 in three years at Monmouth. If one of them engineers a significant turnaround at their current school and follows it with more success elsewhere, their role as "family" members might get them a look in Chapel Hill.

Hubert Davis, North Carolina assistant coach. He's just two seasons into his coaching career, but he scored 1,615 points for the Tar Heels from 1988-92 and then spent 12 seasons playing in the NBA before becoming a familiar face as a TV analyst on ESPN. If the 44-year-old Davis is being groomed, fine, but his candidacy again might depend on how much Williams – and by extension Davis himself – is touched by the investigation into the alleged academic improprieties.

John Groce, Illinois head coach.Groce, 42, has been a Midwest guy with assistant stops at Butler, Xavier and Ohio State before head coaching gigs at Ohio and now Illinois, but he did spend 1996-2000 as an N.C. State assistant. His results in Champaign have been mixed – two 20-win seasons and a 15-21 Big Ten record – but Groce has some time to change that. One or two major runs by his Fighting Illini would make him a hotter commodity.

JerodHaase, Alabama-Birmingham head coach. Haase is a Williams guy through and through, having both played for and coached under Williams at Kansas before moving along to North Carolina as an assistant under Williams in April 2003. That's either a major plus or a total disqualifier, depending on how the NCAA's investigation shakes out. If Williams is implicated in the end, it might poison every branch of his coaching tree. If not? Haase, 40, needs to create or maintain momentum at UAB, where he took the Blazers from 13 wins in his first season of 2012-13 to 18 in 2013-14 -- including an upset of the Tar Heels -- though he has posted identical 7-9 records in Conference USA in both years.

George Karl, longtime NBA head coach.Karl is North Carolina family, having played for the Tar Heels from 1970-73, and he has a marquee name with the NBA pedigree of 1,131 wins as a head coach at the pro level. He was thought to be a contender when Williams turned down the job in 2000, but he had to withdraw his name from consideration when then-Bucks owner Herb Kohl wouldn't let Karl pursue what he called his "dream job" in Chapel Hill. Karl is now 63 years old and has battled cancer. He could offer short-term stability, but one wonders if UNC would seek a more long-range answer.​

Chris Mack, Xavier head coach. This requires some daisy-chain logic based on UNC athletic director Bubba Cunningham's past, so just stick with us here. Cunningham and Georgia Tech AD Mike Bobinski were both former Notre Dame administrators. While Bobinski was Xavier's AD, he promoted Mack to the head coaching job. One could imagine Bobinski assuring Cunningham that the 44-year-old Mack checks off a lot of boxes for what Cunningham would want in a head coach, among them youth, experience and success. Mack is a Cleveland native who has spent most of his career in the Midwest, but he does have a short stint as a Wake Forest assistant on his resume. And he has won 66 percent of his games and made four NCAA tournament berths in five seasons at his alma mater. He could surface as a candidate regardless of NCAA trouble, but given the right contract security, Mack might be willing to take over a beleaguered program with tremendous potential.

Sean Miller, Arizona head coach. He'd surely sit near the top of the wish list, if not outright representing the favored choice of Tar Heels faithful. He's won 72 percent of his games at Xavier and Arizona, and he's drawing elite talent to Tucson on a conveyor belt: CBS noted recently that Arizona's 10 five-star signees in the past five recruiting classes is outpaced only by Kentucky's 16. So the question isn't whether UNC wants Miller. It's whether Miller already has a job that's as good or better. He has a machine humming with the Wildcats, who were No. 1 for a large chunk of 2013-14 and should be title contenders again next season. He has a lucrative and creative contract through 2019 that includes a small stake in an oil and gas company that's currently worth more than $6 million, which he gets in a lump sum if he stays through the end of the deal. Miller has it good enough at Arizona to raise doubt about whether it would be any better in Chapel Hill.​

Chris Mooney, Richmond head coach. The 41-year-old Mooney is 166-132 as Richmond's head coach, which probably sends no jolts of giddiness through the minds of North Carolina's faithful. The Spiders made the Sweet 16 in 2011 but haven't returned to the NCAA tournament since, so that is a trend that would have to change in order for Mooney to become a realistic option. If it does, Cunningham would find a candidate familiar with the region who has Princeton on his curriculum vitae (Mooney played there from 1990-94). In case of NCAA trouble, Mooney's Ivy League stamp might help, but it won't be enough by itself if he hasn't won enough.

Kevin Ollie, Connecticut head coach. If the NCAA comes down hard on the Tar Heels, it's difficult to envision Ollie departing his alma mater and the place that gave him a shot as a head coach. He already had to operate under NCAA restrictions at UConn, overcoming a tournament ban in his first season of 2013 to win the national championship in his second year last April. If this reopened investigation in Chapel Hill passes? Then he'd have to be near the top of the list, and he could be enticed by the bigger ACC stage, assuming conference realignment hasn't sprung UConn from the AAC and that Ollie himself isn't cashing an NBA paycheck by then.

Brad Stevens, Boston Celtics head coach. No doubt a program like North Carolina will take the biggest swings it can at candidates, because it probably (and justifiably) believes it can get them. There's just about zero chance that Stevens would jump to a program besieged by NCAA sanctions, but if UNC is in the clear, it might be an option if Stevens is ever looking to return to the collegiate ranks. He is still just 37 years old and one season into a six-year deal to coach in Boston, but his track record -- two NCAA title game appearances at Butler -- speaks for itself, he'd be an impeccable face of the program and his NBA pedigree will help with recruiting.

Monty Williams, New Orleans Pelicans head coach. Williams hasn't coached a moment in college since his career on the sideline started, but he has coached under Mike Krzyzewski with USA Basketball. He's also a Notre Dame graduate, having played in South Bend from 1989-94, which overlaps with the early days of Cunningham's career a Fighting Irish administrator. Williams is only 42, so he offers a long-term option with NBA credibility for the top-flight recruits North Carolina expects to contend for, and land. The obvious catch is that he probably has to be fired in New Orleans for this to occur. But if he is available, whether the Tar Heels' basketball program is in trouble or not, one could imagine Williams sliding in as coach for a boss with whom he has some familiarity.